MicroRNA let-7d is a target of cannabinoid CB1 receptor and controls cannabinoid signaling.

“Cannabinoid CB1 receptor, the molecular target of endocannabinoids and cannabis active components, is one of the most abundant metabotropic receptors in the brain. Cannabis is widely used for both recreational and medicinal purposes.

Despite the ever-growing fundamental roles of microRNAs in the brain, the possible molecular connections between the CB1 receptor and microRNAs are surprisingly unknown. Here, by using reporter gene constructs that express interaction sequences for microRNAs in human SH-SY5Y neuroblastoma cells, we show that CB1 receptor activation enhances the expression of several microRNAs, including let-7d.

Taken together, these findings provide the first evidence for a bidirectional link between the CB1 receptor and a microRNA, namely let-7d, and thus unveil a new player in the complex process of cannabinoid action.”


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Abrupt Quitting of Long-term Heavy Recreational Cannabis Use is Not Followed by Significant Changes in Blood Pressure and Heart Rate.

“To shed more light on the role of heart rate and blood pressure during cannabis withdrawal.

Abrupt cessation of recreational long-term daily cannabis use was not followed by significant changes in heart rate, blood and pulse pressure.

Also, these measures were not significantly correlated with the severity of the cannabis withdrawal syndrome.

The cohort’s risk for CVD was moderate (all tobacco using, overweight in 9 of 35 patients and elevation of serum C-reactive protein in many patients).

Its metabolic risk for CVD was minor considering the mostly normal blood pressure, normal serum lipids and glucose.


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Chronic administration of Δ9-tetrahydrocannabinol induces intestinal anti-inflammatory microRNA expression during acute simian immunodeficiency virus infection of rhesus macaques.

“Recreational and medical use of cannabis among human immunodeficiency virus (HIV)-infected individuals has increased in recent years. In simian immunodeficiency virus (SIV)-infected macaques, chronic administration of Δ9-tetrahydrocannabinol (Δ9-THC) inhibited viral replication and intestinal inflammation and slowed disease progression…

These results support a role for differential miRNA induction in THC-mediated suppression of intestinal inflammation. Whether similar miRNA modulation occurs in other tissues requires further investigation.


Gastrointestinal (GI) tract disease/inflammation is a hallmark of HIV/SIV infection.

Previously, we showed that chronic treatment of SIV-infected macaques with Δ9-tetrahydrocannabinol (Δ9-THC) increased survival and decreased viral replication and infection-induced gastrointestinal inflammation.

Here, we show that chronic THC administration to SIV-infected macaques induced an anti-inflammatory microRNA expression profile in the intestine…

Overall, our results show that selective upregulation of anti-inflammatory miRNA expression contributes to THC-mediated suppression of gastrointestinal inflammation and maintenance of intestinal homeostasis.”



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Δ9-Tetrahydrocannabinol Treatment During Human Monocyte Differentiation Reduces Macrophage Susceptibility to HIV-1 Infection

“The major psychoactive component of marijuana, Δ9-tetrahydrocannabinol (THC), also acts to suppress inflammatory responses. Receptors for THC, CB1, CB2, and GPR55, are differentially expressed on multiple cell types including monocytes and macrophages, which are important modulators of inflammation in vivo and target cells for HIV-1 infection. Use of recreational and medicinal marijuana is increasing, but the consequences of marijuana exposure on HIV-1 infection are unclear. Ex vivo studies were designed to investigate effects on HIV-1 infection in macrophages exposed to THC during or following differentiation.

THC treatment of primary human monocytes during differentiation reduced HIV-1 infection…

THC treatment of monocytes during differentiation into MDMs suppresses HIV-1 infection. 
Ultimately, the mechanism of THC suppression of HIV-1 infection was traced to a reduction in cell surface HIV receptor (CD4, CCR5 and CXCR4) expression that diminished entry efficiency.”


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Wired to run: exercise-induced endocannabinoid signaling in humans and cursorial mammals with implications for the ‘runner’s high’

“Humans report a wide range of neurobiological rewards following moderate and intense aerobic activity, popularly referred to as the ‘runner’s high’, which may function to encourage habitual aerobic exercise. Endocannabinoids (eCBs) are endogenous neurotransmitters that appear to play a major role in generating these rewards by activating cannabinoid receptors in brain reward regions during and after exercise…”

Recent work supports direct links between eCB signaling and exercise in humans…

It is possible that neurobiological rewards induced by eCB signaling are an ancient human trait that evolved to encourage aerobic activity, and that the rewards explain the evolution…

The fact that running, and endurance exercise in general, remains an enjoyable and psychologically beneficial recreational activity for tens of millions of humans today suggests that we still may respond to a neurobiological trait that evolved early in our lineage.”


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Plant, synthetic, and endogenous cannabinoids in medicine.


“Although used for more than 4000 years for recreational and medicinal purposes, Cannabis and its best-known pharmacologically active constituents, the cannabinoids, became a protagonist in medical research only recently. This revival of interest is explained by the finding in the 1990s of the mechanism of action of the main psychotropic cannabinoid, Delta9-tetrahydrocannabinol (THC), which acts through specific membrane receptors, the cannabinoid receptors. The molecular characterization of these receptors allowed the development of synthetic molecules with cannabinoid and noncannabinoid structure and with higher selectivity, metabolic stability, and efficacy than THC, as well as the development of antagonists that have already found pharmaceutical application. The finding of endogenous agonists at these receptors, the endocannabinoids, opened new therapeutic possibilities through the modulation of the activity of cannabinoid receptors by targeting the biochemical mechanisms controlling endocannabinoid tissue levels.”


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